1. Field of the Invention
This invention relates to improvements in disposable flexible liners for material handling and discharge bags as well as a method of releasably installing such a liner in a bag.
2. Prior Art
Material-handling and discharge bags of the dual-walled, pneumatically-assisted discharge type have been pioneered by All-Flow, Inc. of Buffalo, NY. Such bags are disclosed, for example, in U.S. Pat. Nos. 4,421,250, 4,449,646 and 4,476,998 and have been successfully installed and operated in both the stationary mode and transportation mode, e.g., in convertible trailers for converting such trailers from piece goods to bulk goods, see European Patent Application Publication No. 0121419 and corresponding U.S. Pat. No. 4,534,596.
Although the All-Flow bags for handling granular flexible material have in general a self-cleaning function accomplished by the flexing of the bag, there are times when it is desired to use the bags for very diverse materials on subsequent trips, e.g., fertilizer and edible grains for example. Also, certain materials are viscous and sticky, particularly certain liquids, and even though the bag is self-cleaning in granular materials, it would need washing out when handling sticky viscous materials such as molasses or the like. The cleaning of storage bags after a trip to remove sticky material for a subsequent trip is a very time-consuming manual operation and hence is quite expensive. Moreover, it is practically impossible to obtain sterile cleanliness even with steam-cleaning of storage bags.
Accordingly, there is an unfulfilled need in the art for a disposable liner for material-handling and storage bags which liner is of an inexpensive material so it could be disposed after each use, but could be quickly and easily installed and removed. This would eliminate the cleaning problem and would also eliminate a sanitation problem involving different loads of incompatible materials. Although there was a need for such in the art, Applicant is unaware of any attempts to fulfill such need. Various problems are faced such as having a liner which would conform to the walls of the material storage bag and stay there during installation and then be removable after discharge while at the same time being expandable and inexpensive enough to allow it to be disposed of after each use.